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Flood Management

River Forecasting


Under the authority of the California Water Code Section 236, the River Forecasting Section works with the National Weather Service's California-Nevada River Forecast Center to provide year-round daily forecasts of reservoir inflows, river flows, and water levels throughout California and in parts of Nevada. These forecasts are used by the Flood Operations Branch and the National Weather Service to determine the level of joint Federal-State flood response activation and operations. During high water events, Federal and State river forecasters work around the clock to update their forecasts and monitor real-time changes in California and Nevada's larger rivers and estuaries.

The Section, in cooperation with the National Weather Service, also produces astronomical tide tables for the Sacramento-San Joaquin Delta. These tide forecasts are used by recreational boaters and cargo transport to two of California's deep water port facilities, the Port of Stockton and the Port of Sacramento. These forecasts are also used to schedule operations of the State Water Project's Delta Pumping Plant in order to minimize project operations on local water levels. These annual astronomical forecasts are then adjusted daily to account for local weather (wind and pressure) and high outflow conditions.

The Section also functions as a center of technical expertise on watershed hydrology, and river and estuary-based hydrodynamics by supporting other Department and public inquires.